Hi, has anyone else had this problem. I was playing a gig last night in a function room with an 'star lit' dance floor (little LEDs embedded into it) but anytime I went near it my IEMs would howl and I'd get a mains 50hz hum from FOH. I got around it by keeping away from the dance floor but I'm wondering what I could do to stop it happening in future (what did other people do stop stop it happening?). Thanks. For info I use: Fender P special, markbass little mark 500 and markbass 2x10 traveller, Zoom b3 pedal, gear4music iem.